Fun Hesperornis Facts For Kids

Nidhi Sahai
Oct 20, 2022 By Nidhi Sahai
Originally Published on Oct 04, 2021
Edited by Jacob Fitzbright
Discover amazing Hesperornis facts from our article to learn about this prehistoric creature.
Age: 3-18
Read time: 6.3 Min

Hesperornis means a ‘western bird’. They are a genus of cormorant resembling birds.

Their existing period was the first half of the Campanian age of the Late Cretaceous period. The areas of marine limestones from Kansas and marine shales from Canada are some locations for the Hesperornisfossils.

There were in total nine species that got recognized out of which eight were recovered from rocks in North America (western Kansas) and one of them from Russia.

These birds were definitely active swimmers who used their efficient ability to chase and prey on fish. They lived less on land.

Many features skeleton of these birds used to resemble present-day loons. They had small wings that were quite useless for flight, and the bones of the wings were spintlike. They had a feathered body.

Their breastbones did not have the keel which used to serve as an anchor for powering flight muscles. The legs were very powerful and were efficient in swimming and diving in the water.

For more fascinating facts, keep reading, and check out more interesting facts about other dinosaurs like the Diatryma and Confuciusornis. 

Hesperornis Interesting Facts

Was the Hesperornis a dinosaur?

The Hesperornis was not a dinosaur. It was a bird. They had appearances like that of half-bird and half-dinosaur.  They were medium-sized fish-eating birds. The first specimen of this bird was found by Othniel Charles Marsh in the year 1871. They were fish-eating birds.

How do you pronounce 'Hesperornis'?

The pronunciation of these primitive and aquatic fish-eating birds is 'Hess-per-or-niss'. These birds were very proficient in swimming and being on the water, walking on the land was an awkward task for them.

What type of prehistoric animal was a Hesperornis?

Hesperornis was a bird of the phylum Chordata, clade Dinosauria, family Hesperornithidae, and genus Hesperornis. They had sharp teeth and were fish-eating birds. They were 5.9 ft (1.8 m) in length and were toothed, flightless birds.

In which geological period did the Hesperornis live?

They were in existence millions of years ago. Hesperornis lived in the Late Cretaceous period, the first half of the Campanian age, which was somewhere between 99.6- 65.5 million years ago. Most of the remains of this bird have been found in the great plains area of the United States and a few of them in Alaska.

When did the Hesperornis become extinct?

The exact account of their extinction is not known yet. They went extinct around 70-80 million years ago during or after the Cretaceous period. Their relation with modern birds is still not quite known.

Where did a Hesperornis live?

These flightless and feathered body aquatic birds might have lived in present-day North America (western Kansas) as most of the fossils have been collected from there, which shows that they were endemic. Apart from that, Alaska is also considered as one of their habitats. Some fossils have also been found in Europe, Mongolia, and Kazakhstan.

What was a Hesperornis habitat?

These birds were creatures of the water and used to spend most of their time near or in the water. They used to walk on land very awkwardly with their feet and legs and used to catch prey around the water region, which was warmer than the current climate. They used their hind legs for swimming.

Who did a Hesperornis live with?

These marine birds were content to ignore animals and survivors, until and unless they tend to get close for comfort. They used to devour fishes such as Coelacanths but were hunted down by predators.

How long did a Hesperornis live?

The lifespan of Hesperornis is not known yet after the study of their fossils. They used to inhabit the areas of the great plains and water areas which is in present-day North America and they lived during the Late Cretaceous period.

How did they reproduce?

These flightless birds were oviparous and used to lay eggs. The Hesperornis egg was interesting as they used to lay both white-brown eggs and golden eggs. They used to harvest and kill many fishes, before laying eggs on the ground.

Hesperornis Fun Facts

What did a Hesperornis look like?

These birds from a million years ago are the fish-eating birds that used to live in the region of water bodies.

Hesperornis was a very large bird that could attain a length of 5.9 ft (1.8 m). It is believed that they had no absolute wings and used their hind legs to swim.

Their appearance was like a mixture of dinosaur and loon. They had similar long necks like that of a loon and waterproof feather switch strong webbed feet that used to propel them through the water.

They had one distinguishing feature from the loons that they used to have vestigial wings (flight preventing wings) and also had a very small tooth almost like a needle to helo them catch fish. They specifically didn't really like land.

They used to live in the late cretaceous period. Many features of the skeleton of these birds resemble present-day loons.

How many bones did a Hesperornis have?

There is no accurate count of the number of bones in the Hesperornis' skeleton. Their slender long neck gave them a silhouette on the water which is similar to a modern-day grebe. They would have fed and bred very much like a penguin. Modern birds might have some relation to them.

How did they communicate?

There is no information available on the communicating skills of the Hesperornis.

How big was a Hesperornis?

Hesperornis was one of the earliest giant marine predators of North America and was 5.9 ft (1.8 m) in length.  One of the largest Hesperornithiformes was Canadaga Arctica which was named and described in 1999 and might have attained a height of over 5 ft (1.5 m).

How fast could a Hesperornis fly?

Although Hesperornis had somewhat wing-like bone structures, they couldn't help them fly. The vestigial wings even prevented them from flying. These birds were great swimmers and proficient in diving.

How much did a Hesperornis weigh?

These dinosaurs like birds of the cretaceous period Hesperornis (Hesperornis regalis) weighed around 275.57-310.85 lb (125-141 kg). The first specimen of this bird was found by Othniel Charles Marsh in the year 1871.

What were the male and female names of the species?

There are no specific names for the male and the female of this dinosaur species of North America Hesperornis (Hesperornis regalis).

What would you call a baby Hesperornis?

The baby of this meat-eating bird species Hesperornis (Hesperornis regalis) does not have any particular name to be called by.

What did they eat?

Hesperornis had long jaws with many small sharp teeth. They were marine predators who liked to eat fish, belemnites, and ammonites. Hesperornis had very long legs with webbed feet and a feathered body. Their wings were very small in size and they used them for steering when diving underwater rather than flying.

How aggressive were they?

The information on their aggressive behavior is quite not known as of now but the very close species of Ichthyornis were considered as an aggressive species of bird.

Did you know...

There were in total nine species of Hesperornis that were recognized, out of which eight were recovered from rocks in North America and one of them from Russia. The nine species are H. regalis, H. crassipes, H. gracilis, H. altus, H. montana, H. rossicus, H. bairdi, H. chowi, H. macdonaldi, H. mengeli, and H. lumgairi.

Did Hesperornis have teeth?

Just like most of the Mesozoic birds like Ichthyyornis, the Hesperornis species also had teeth and a beak. Their teeth were present near the lower jaw and at the back of the upper jaw. They were toothed birds who had really sharp teeth.

Could the Hesperornis fly?

Being a bird with almost no flight-supporting wings, these prehistoric birds were flightless. Their vestigial wings were the reason that prevented them from flying. They were adapted to that and had very long legs with webbed feet and they used their hind legs for swimming.

Here at Kidadl, we have carefully created lots of interesting family-friendly dinosaur facts for everyone to discover! Learn more about some other dinosaurs from our Diplocaulus facts and Metamynodon facts pages.

You can even occupy yourself at home by coloring in one of our free printable Hesperornis coloring pages.

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Written by Nidhi Sahai

Bachelor of Arts in Journalism and Mass Communication

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Nidhi SahaiBachelor of Arts in Journalism and Mass Communication

Dedicated and experienced, Nidhi is a professional content writer with a strong reputation for delivering high-quality work. She has contributed her expertise to esteemed organizations, including Network 18 Media and Investment Ltd. Driven by her insatiable curiosity and love for journalism and mass communication, Nidhi pursued a Bachelor of Arts degree from Guru Gobind Singh Indraprastha University, graduating with distinction in 2021. During her college years, she discovered her passion for Video Journalism, showcasing her skills as a videographer for her institution. Nidhi's commitment to making a positive impact extends beyond her professional pursuits. Actively engaging in volunteer work, she has contributed to various events and initiatives throughout her academic career.

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